Air bleeding pipe joint

Abstract

An air bleeding pipe joint has a pair of connection pipe portions inserted and connected to a circulation piping of engine cooling water, a branch pipe portion branched from the connection pipe portions and having an air bleeding hole in an inner side thereof, and a plug body detachably mounted to the branch pipe portion, and opening and closing the air bleeding hole. The air bleeding pipe joint discharges air within the circulation piping to the outside by opening the air bleeding hole. The plug body is attached to the branch pipe portion by using an elastic locking structure or an embedding structure.

1 . An air bleeding pipe joint, comprising: 
 (a) a pair of connection pipe portions inserted and connected to a circulation piping of engine cooling water;    (b) a branch pipe portion branched from said connection pipe portion and having an air bleeding hole in an inner side thereof;    (c) a plug body detachably mounted to said branch pipe portion, and opening and closing said air bleeding hole;    the air bleeding pipe joint discharging air within said circulation piping to the outside by opening said air bleeding hole,    wherein said plug body is attached to said branch pipe portion by using an elastic locking structure or an embedding structure.    
   
   
       2 . An air bleeding pipe joint as claimed in  claim 1 , wherein said plug body is attached to said branch pipe portion by using said elastic locking structure, and said elastic locking structure is structured such that an elastic locking hook is provided in one of said plug body and said branch pipe portion, a locking portion elastically locking said elastic locking hook is provided in the other, and said plug body is capable of being attached to and detached from said branch pipe portion, by locking said elastic locking hook to said locking portion and canceling the locking.  
   
   
       3 . An air bleeding pipe joint as claimed in  claim 2 , wherein said plug body has an insertion portion to said branch pipe portion, said elastic locking hook is provided in said insertion portion, and said locking portion is provided at a corresponding position of said branch pipe portion.  
   
   
       4 . An air bleeding pipe joint as claimed in  claim 3 , wherein said branch pipe portion is provided with an operation window for canceling the elastic locking of said elastic locking hook to said locking portion.  
   
   
       5 . An air bleeding pipe joint as claimed in  claim 2 , wherein a one-way annular come-off prevention tooth having a saw-tooth cross-sectional shape is provided in an outer peripheral surface of said connection pipe portion, said come-off prevention tooth allows a relative movement of said connection pipe portion in an inserting direction with respect to said circulation piping, and eats into an inner surface of said circulation pipe in a reverse direction so as to achieve a come-off prevention.  
   
   
       6 . An air bleeding pipe joint as claimed in  claim 1 , wherein said plug body is attached to said branch pipe portion by using said embedding structure, and said embedding structure is structured such that a female thread portion is provided in an inner surface of said branch pipe portion, a male thread portion is provided in said plug body, they are coupled by screw, an engagement concave portion for engaging a tool is provided in a top surface of said plug body, and said plug body is entirely embedded inside said branch pipe portion.  
   
   
       7 . An air bleeding pipe joint as claimed in  claim 6 , wherein said engagement concave portion is formed in a hexagonal shape.  
   
   
       8 . An air bleeding pipe joint as claimed in  claim 6 , wherein a large-diameter head portion is provided in said plug body, an accommodation portion accommodating said head portion is provided in said branch pipe portion, and a bottom surface of said accommodation portion is formed as a stopper surface defining a screwing amount of said plug body.